The Giants went with the theory that you cannot have too many pass rushers when they selected Mathias Kiwanuka in the first round of the NFL Draft.

Before they made the pick, Justin Tuck might have agreed.

Now, the second-year defensive end is not so sure.

“I think we got enough right now,” Tuck said yesterday.

He smiled faintly as he spoke, knowing well that the addition of Kiwanuka means a potential diminution of his playing time.

The surprising thing was not that the Giants deemed Kiwanuka worthy of the final pick in the first round (they traded down to No. 32 to get him), but that they added him to an already well-stocked stable of defensive ends.

Michael Strahan and Osi Umenyiora are Pro Bowlers and double-digit sack artists, and in Tuck the Giants have a promising sophomore who contributed as a rookie and looks to be a keeper.

The Giants want Kiwanuka – Boston College’s all-time sack leader – to immediately get on the field in some specialized role, and if he does, there’s no way that won’t adversely affect Tuck’s playing time.

Even if Tuck is pushed inside to tackle in certain pass-rushing situations, it is difficult to view this development as a positive reflection on him.

“After the pick came up, I got called from a couple of coaches letting me know it doesn’t affect me,” Tuck said, displaying no apparent acrimony. “It wasn’t a reflection on how they view me as a player. I don’t view this pick as a me-and-him issue. Obviously it’s going to create competition, and who says that’s not a good thing?” That the Giants went for defense in the first round surprised no one; that they went for another end, however, caught many off guard.

“They have their reasons for doing things; I might not understand it, but they have their own reasons and you got to live with it,” said Umenyiora, who is close with Tuck. “I’m not going to question their judgment. Everybody laughed at them when they drafted me.” Still, he admitted, “It looks like it might stunt somebody’s growth.” Tuck sounds as if he’s up to the challenge.

“I can see why we picked him,” Tuck said of Kiwanuka.

“Great athlete, and to get him at No. 32, it could be a steal. He’s going to improve our defense, simple as that.

“It’s competition,” Tuck added. “Hopefully, we can bring out the best in each other.”